↑Beckwith, Christopher. (2009). Empires of the Silk Road: A History of Central Eurasia from the Bronze Age to the Present. Princeton and Oxford: Princeton University Press. ISBN 978-0-691-13589-2. Page 63.

↑Cyrus's date of death can be deduced from the last two references to his own reign (a tablet from Borsippa dated to 12 August and the final from Babylon 12 September 530 BC) and the first reference to the reign of his son Cambyses (a tablet from Babylon dated to 31 August and or 4 September), but a undocumented tablet from the city of Kish dates the last official reign of Cyrus to 4 December 530 BC; see R. A. Parker and W. H. Dubberstein, Babylonian Chronology 626 B.C. – A.D. 75, 1971.

↑The Cambridge Ancient History Vol. IV p. 42. See also: G. Buchaman Gray and D. Litt, The foundation and extension of the Persian empire, Chapter I in The Cambridge Ancient History Vol. IV, 2nd edition, published by The University Press, 1927. P. 15. Excerpt: The administration of the empire through satrap, and much more belonging to the form or spirit of the government, was the work of Cyrus ...